VANCOMYCIN RESISTANT ENTEROCOCCI IN PATIENTS ON PROLONGED HOSPITALIZATION IN LAGOS UNIVERSITY TEACHING HOSPITAL, NIGERIA

Abstract

Enterococci are responsible for up to 12% of cases of healthcare associated infections
worldwide and cause life threatening infections among critically ill patients. They show
intrinsic and acquired resistance to a wide range of antimicrobial agents. Glycopeptide
resistance is due to vanA, vanB, vanC, vanD, vanE, vanG and vanL genes.
The objectives of this study were to determine the carriage rate of VRE among patients on
prolonged hospitalization in LUTH, assess the antimicrobial resistance pattern of VRE,
identify factors associated with VRE colonization and describe the genetic determinants of
enterococcal resistance to Vancomycin
VRE were isolated from rectal swabs collected from patients hospitalized for seven days or
more in Lagos University Teaching Hospital and identified by Matrix Assisted Laser
Desorption Ionization (MALDI) and Polymerase Chain Reaction (PCR). Antimicrobial
susceptibility testing was performed by E-test. PCR assay for Vancomycin resistance genes
was also performed. Data on demographic and risk factors collected by questionnaire was
tested for significance using chi square.
Fourteen out of 329 patients surveyed were colonized with VRE; one with vanA E. faecium,
two with vanB E. faecium, ten with E. gallinarum and one with E. casseliflavus. Univariate
analysis for risk factors associated with VRE colonization was only significant for the ward
of admission. Only one VRE isolate showed full resistance to vancomycin and Teicoplanin.
Three were resistant to Ampicillin and nine to Ciprofloxacin but all were susceptible to
Linezolid. High-level resistance to Gentamicin was found in four VRE isolates.
There is a low prevalence of VRE in Lagos University Teaching Hospital which may be
spreading among patients in affected wards.